This invention relates to a motorcycle construction and more particularly to an improved motorcycle layout and a layout for a motorcycle wherein at least some of the running components are enclosed and protected.
As is well known, a motorcycle generally is comprised of a frame assembly that dirigibly supports a front wheel and which journals a driven rear wheel. The rear wheel is driven by an engine that is mounted in the frame assembly in a suitable manner between the front and rear wheels. In connection with the improvement of the performance and handling of a motorcycle, it is, of course, desirable to provide a low center of gravity for the machine. One way that this can be done is by inclining the engine from the vertical. However, with many types of applications, it is desirable to insure that the engine be well protected.
For example, a frequent use for motorcycles is with a form of competition known as motocrossing. In such competition, the motorcycle encounters extremely rough terrain. Accordingly, it is the normal practice to have a fairly high frame position relative to the ground. However, with such a motorcycle when the engine is inclined from the vertical and toward the horizontal, many of the critical components of the engine may be positioned so that they could be damaged which would adversely effect the performance and have other obvious disadvantages.
It is, therefore, a principal object of this invention to provide an improved motorcycle arrangement wherein a low center of gravity can be achieved and yet the critical components of the engine are protected.
It is a further object of this invention to provide an improved layout for a motocross type motorcycle.
It is yet another object of this invention to provide a motorcycle construction of the type wherein the engine is inclined from the vertical toward the horizontal and wherein the intake and exhaust system extend rearwardly from the engine and are protected by it.
One type of frame assembly that is utilized widely in racing machines is the type of frame that has a head pipe that journals the front wheel and a pair of angularly extending main frame members that are fabricated from boxlike sections. These members extend generally downwardly and rearwardly to a casting or other fabrication which journals the rear wheel for its suspension movement. With such an arrangement, it should be obvious that a forward inclination of the engine will place the engine in an extremely exposed area. It is, therefore, a still further object of this invention to provide an improved arrangement for protecting an engine that is inclined from the vertical and which is used in a frame assembly of the type as aforedescribed.
It is a further object of this invention to provide an improved, simplified and yet effective way of protecting an engine in a motorcycle having a fabricated box section type of frame assembly.
When the motorcycle engine is protected by some form of covering, however, this gives rise to still additional problems. For example, if the induction system is disposed rearwardly, then it can be difficult to provide adequate air flow to the engine induction system, particularly if the engine is enclosed.
It is, therefore, a still further object of this invention to provide an improved induction system for a motorcycle of the type as aforedescribed.